Cardiovascular stents are widely used in the treatment of vascular diseases. For example, stents have been broadly implanted in vessels to treat vessel narrowing, occlusion, aneurysm, and dissection, among other conditions. A typical conventional or known stent contains a metallic mesh material that is mounted or carried on a deflated balloon. In the center of the balloon is a channel, through which a guidewire can pass to facilitate movement through the arteries; however, there is no channel or space between the metallic mesh material and the balloon. A guidewire is inserted to the vessel and pass the location that needs to be treated and then the cardiovascular stent mounted or carried on a deflated balloon is inserted into the vessel and delivered to the desired location through this guidewire to facilitate movement through the arteries. When the stent is at the desired location, the balloon is inflated to expand and, thereby, deploy the stent to support the artery.
Vessels have branches; when narrowing, these narrowed branches are referred to as “bifurcation lesions”. When treating a bifurcation lesion with a conventional or known stent, one guidewire is delivered to the main branch, and another guidewire is delivered to a side branch. After the stent is delivered and deployed at a bifurcation lesion, the guidewire in the side branch should be pulled back from the space between the metallic mesh material and the vessel wall and then sent into the main branch through the lumen of the stent. Thereafter, another wire from the main branch should also be pulled back and sent to the side branch through the metallic mesh from the lumen of the stent in the vessel. This procedure is called “wire-exchange”. This “wire-exchange” procedure is complicated and time-consuming.
In addition, when an ostial lesion (usually defined as a lesion within 3 mm of the ostium of the vessel at the aorto-ostial or branch-ostial junction) is treated, a typical conventional or known stent has to be deployed precisely at the desired location. To ensure precise deployment at the desired location, some operators like to employ the Szabo technique1: specifically, they inflate part of the balloon with low pressure, and then deflate the balloon to allow the guidewire to pass through the space between the metallic mesh material and the balloon for the precise deployment of the stent. However, this procedure has a risk of stent dislodgement1.
U.S. Pat. No. 8,771,342 issued Jul. 8, 2014 to Vardi is of interest for showing the background of this type of invention, and this reference is hereby incorporated herein in its entirety. In this reference, a method of deploying a stent in a bifurcation is shown that includes introducing two guidewires through the main vessel and using the two guidewires for guiding a dual lumen catheter carrying a stent first to an initial position proximal to the stent deployment position, retracting one wire, and projecting it from the catheter and through a side of the stent a branch guidewire into the second branch vessel, and then moving the catheter to the predetermined deployment position while guided by the main guidewire in the first branch vessel, and the branch guidewire in the second branch vessel. The stent is then expanded, and the catheter is removed with the stent remaining in its deployed position An alternative embodiment includes introducing one wire, advancing the system over the one wire and subsequently introducing the second wire.
U.S. Pat. No. 7,771,462 issued Aug. 10, 2010 to Davidson, et al. is of interest for showing the background of this type of invention, and this reference is hereby incorporated herein in its entirety. This reference describes a designed catheter system comprises a catheter having a catheter body with a distal end, a proximal end, a main vessel guidewire lumen for receiving a main vessel guidewire and a balloon disposing at the distal end of the catheter body. The catheter further includes a side member that is disposed adjacent to the catheter body. The side member has a distal end, a proximal end, and a branch vessel guidewire lumen for receiving a branch vessel guidewire. A stent having a side hole is disposed over the balloon, and a distal portion of the side member is disposed beneath at least a portion of the stent while being adjacent to and movable with respect to the balloon.
U.S. Pat. No. 8,828,071 issued Sep. 9, 2014 to Bourang et al is of interest for showing the background of this type of invention, and this reference is hereby incorporated herein in its entirety. This references discusses a system for treating a bifurcation that includes first and second delivery catheters, each having an expandable member. A stent having a side hole is disposed on the second delivery catheter. A portion of the first delivery catheter is disposed under a portion of the stent. The first delivery catheter is slidable relative to the second delivery catheter, and the first delivery catheter passes through the side hole. Expansion of the first expandable member expands a proximal portion of the stent in a main branch vessel, and expansion of the second expandable member expands a distal portion of the stent in a side branch vessel.
U.S. Pat. No. 8,808,347 issued Aug. 19, 2014 to Bourang et al is of interest for showing alignment of the side branch stent with the main branch stent, and this reference is hereby incorporated herein in its entirety. This reference describes a system for treating a bifurcation includes a first radially expandable stent and a second radially expandable stent. The first stent has a side hole and a plurality of lateral elements extending from the side hole. The second stent has a plurality of axial elements extending away from the proximal end of the second stent. The axial elements of the second stent interdigitate with the lateral elements of the first stent when both stents have been expanded.
U.S. Pat. No. 8,795,347 issued Aug. 5, 2014 to Bourang et al is of interest for showing methods and systems for treating a bifurcation with provisional side branch stenting.
There is a need for a newly designed stent to overcome the shortcomings of the typical conventional or known stent.